Question

Helen purchased 3 copies of a book online at a 20% discount. She also paid $10 for shipping that was not discounted. How much was the original price of one copy of the book if her total ended up being $40?

Answer 1

Answer:

The original price of the book was $12.50

Step-by-step explanation:

3x - 0.2(3x) + 10 = 40
30x - 2(3x) + 100 = 400
   30x - 6x + 100 = 400
           24x + 100 = 400
                     24x = 300
                         x = 12.50